yes, drinking water can kill you. but you have to be talking measuring your drinking in gallons per hour [which you aren't] and you need to be not urinating as well.
there are certain medical conditions where you should be limiting your water consumption, but you'd already be under a doctor's care and advised of that if it were the case.
as far as how much you should be drinking, it's the amount you're putting out. in other words, if you live in a hot climate and you work out and sweat a lot, 8-10 bottles of water might be a reasonable amount. if you sit at an air conditioned desk and don't move all day, it might be way too much. if your urine is a pale yellow color, you're doing just fine. if your urine is clear, you can scale back how much water you're drinking.
-google first. ask questions later.